package com.itzh.nio.groupchat;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Scanner;
import java.util.Set;

public class GroupChatClient {
    private final String HOST = "127.0.0.1";
    private final int PORT = 6667;
    private Selector selector;
    private SocketChannel socketChannel;
    private String username;

    public GroupChatClient() throws IOException {
        selector = Selector.open();
        //连接服务器
        socketChannel = SocketChannel.open(new InetSocketAddress(HOST,PORT));
        //设置非阻塞
        socketChannel.configureBlocking(false);
        //将channel，注册到selector
        socketChannel.register(selector, SelectionKey.OP_READ);
        username = socketChannel.getLocalAddress().toString().substring(1);
        System.out.println(username+"is ok ....");
    }
    //向服务器发送消息
    public void sendInfo(String info){
        info = username+" 说："+info;
        try{
            socketChannel.write(ByteBuffer.wrap(info.getBytes()));
        }catch (IOException e){
            e.printStackTrace();
        }
    }
    //读取从服务器端回复的消息
    public void readInfo(){
        try{
            int read = selector.select();
            if(read > 0){
                Set<SelectionKey> selectionKeys = selector.selectedKeys();
                Iterator<SelectionKey> iterator = selectionKeys.iterator();
                while(iterator.hasNext()){
                    SelectionKey key = iterator.next();
                    if(key.isReadable()){
                        //得到相关的通道
                        SocketChannel sc = (SocketChannel) key.channel();
                        //得到一个buffer
                        ByteBuffer buffer = ByteBuffer.allocate(1024);
                        //读取
                        sc.read(buffer);
                        String msg = new String(buffer.array());
                        System.out.println(msg.trim());
                    }
                    iterator.remove();
                }
            }else{
                //System.out.println("没有可以用的通道");

            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    public static void main(String[] args) throws IOException {
        GroupChatClient groupChatClient = new GroupChatClient();

        new Thread(){
            @Override
            public void run() {
                while(true){
                    groupChatClient.readInfo();
                    try{
                        Thread.currentThread().sleep(3000);
                    }catch (InterruptedException e){
                        e.printStackTrace();
                    }
                }
            }
        }.start();
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNextLine()){
            String s = scanner.nextLine();
            groupChatClient.sendInfo(s);

        }
    }
}
